Although Web 2.0 tools like blogs and wikis have been used for supporting collaborative learning in higher education, there are not many reports about implementation of that resource on engineering in Brazil. In this ...Although Web 2.0 tools like blogs and wikis have been used for supporting collaborative learning in higher education, there are not many reports about implementation of that resource on engineering in Brazil. In this way, the main purpose of this research is to use a wiki platform for online activities and evaluate how students collaborate with each other in online tasks. It was investigated how collaboration can be measured on wiki platform During four-week online activities, 40 students of Civil Engineering course were monitored on Wikispaces~ platform. All students＇ actions were analyzed and classified as low, medium, or high level of collaboration. The data were collected through the statistical reports of Wikispaces~ and Google Analytics platforms. It computed 336 students＇ actions： 16.67% as high level, 45.24% as medium, and 38.10% as low. During informal interview, most of students （70%） related that wiki was a nice tool for collaboration work. The results indicated that wiki platform is an important way to develop innovative activities and tasks for the purpose of improving engineers＇ abilities and skills such as： writing communication, organization, collaboration, and critical thinking development.展开更多
Studies on soil wind erosion began with single factors affecting soil wind erosion; with increasing quantities of data being accumulated,the wind erosion equation(WEQ),the revised wind erosion equation(RWEQ),the wind ...Studies on soil wind erosion began with single factors affecting soil wind erosion; with increasing quantities of data being accumulated,the wind erosion equation(WEQ),the revised wind erosion equation(RWEQ),the wind erosion prediction system(WEPS),and other soil wind erosion models have been successively established,and great advances have been achieved.Here we briefly review the soil wind erosion research course and analyze the advantages and disadvantages of the current soil wind erosion models.From the perspective of the dynamics of wind erosion,we classified the factors affecting soil wind erosion into three categories,namely,wind erosivity factors(WEF),soil antierodibility factors(SAF),and roughness interference factors(RIF).We proposed the concept of a standard plot of soil wind erosion to solve the problem of uncertainty of the soil wind erosion modulus on a spatial scale,and provided methods to set similarity conditions in wind tunnel simulation experiments and to convert the spatial scale of the wind erosion modulus from the standard plot to a large scale field.We also proposed a conceptual model on the basis of the dynamics of soil wind erosion with the theoretical basis that wind produces a shear force on the soil surface.This shear force is partitioned by barely erodible soil surfaces and roughness elements on the ground,and the amount of soil loss by wind should be calculated by comparing the shear force of the wind on barely erodible soil surfaces with the anti-erosion force of the surface soil.One advantage of this conceptual model is that the calculated soil wind erosion modulus is not subject to changes of spatial scale.Finally,we recommended continual improvement of the existing models while also establishing new models.展开更多
文摘Although Web 2.0 tools like blogs and wikis have been used for supporting collaborative learning in higher education, there are not many reports about implementation of that resource on engineering in Brazil. In this way, the main purpose of this research is to use a wiki platform for online activities and evaluate how students collaborate with each other in online tasks. It was investigated how collaboration can be measured on wiki platform During four-week online activities, 40 students of Civil Engineering course were monitored on Wikispaces~ platform. All students＇ actions were analyzed and classified as low, medium, or high level of collaboration. The data were collected through the statistical reports of Wikispaces~ and Google Analytics platforms. It computed 336 students＇ actions： 16.67% as high level, 45.24% as medium, and 38.10% as low. During informal interview, most of students （70%） related that wiki was a nice tool for collaboration work. The results indicated that wiki platform is an important way to develop innovative activities and tasks for the purpose of improving engineers＇ abilities and skills such as： writing communication, organization, collaboration, and critical thinking development.
基金supported by the National Natural Science Foundation of China(Grant No.41330746)
文摘Studies on soil wind erosion began with single factors affecting soil wind erosion; with increasing quantities of data being accumulated,the wind erosion equation(WEQ),the revised wind erosion equation(RWEQ),the wind erosion prediction system(WEPS),and other soil wind erosion models have been successively established,and great advances have been achieved.Here we briefly review the soil wind erosion research course and analyze the advantages and disadvantages of the current soil wind erosion models.From the perspective of the dynamics of wind erosion,we classified the factors affecting soil wind erosion into three categories,namely,wind erosivity factors(WEF),soil antierodibility factors(SAF),and roughness interference factors(RIF).We proposed the concept of a standard plot of soil wind erosion to solve the problem of uncertainty of the soil wind erosion modulus on a spatial scale,and provided methods to set similarity conditions in wind tunnel simulation experiments and to convert the spatial scale of the wind erosion modulus from the standard plot to a large scale field.We also proposed a conceptual model on the basis of the dynamics of soil wind erosion with the theoretical basis that wind produces a shear force on the soil surface.This shear force is partitioned by barely erodible soil surfaces and roughness elements on the ground,and the amount of soil loss by wind should be calculated by comparing the shear force of the wind on barely erodible soil surfaces with the anti-erosion force of the surface soil.One advantage of this conceptual model is that the calculated soil wind erosion modulus is not subject to changes of spatial scale.Finally,we recommended continual improvement of the existing models while also establishing new models.
